drivers behind the towed vehicle will not be alerted when
the motorhome stops, which may cause a collision.
CAUTION
Unless there is at least ¼" of clearance between the
bulb and the lens, the lens will melt and/or discolor.
3. Drill one-inch circular holes through the back of the
taillight housings at the mounting points you have selected.
The holes must be circular, in order to hold the sockets
in place. A hole saw works best, but the shape and location
of some taillights may require a rotary cutting tool.
Be certain not to cut into any wires or other compo-
nents. Severe electrical damage or injury may result.
4. Bend the spring-loaded tabs that encircle the sockets
outward slightly, then snap the sockets into the holes.
If the tabs are not bent, road vibrations will cause the
sockets to fall out of the holes. For this reason, make certain
the sockets are securely attached before continuing.
Note: if one of the holes is not completely circular, bend
one or more of the tabs farther to accommodate the shape
of the hole.
5. Use the butt connectors to attach the four-wire electrical
harness to the sockets. Figure 1 is ROADMASTER's recom-
mended wiring schematic.
Attach the appropriate wires to either one of the sockets.
Then separate the wires, peel back the appropriate wire(s)
to the other side and attach them in the same manner.
Note: use the larger yellow connectors for two-wire
connections; use the smaller blue connectors for single-wire
connections.
6. Use the ring terminal and the self-tapping screw to
continued on next page
Read all instructions before install-
ing the kit components. Failure to un-
derstand how to properly install the kit
could result in property damage, per-
sonal injury or even death.
Required Tools
• 1" hole saw or rotary cutting tool • drill
• wire stripper • wire crimper • test light
Parts List
• a 6- to 7-wire power cord • (1) 6-wire socket
• a 27-foot four-wire flat • (1) socket bracket
• (2) bulb and socket assemblies • (1) ring terminal
• (3) yellow butt connectors and (3) blue butt connectors
• (1) self-tapping screw • (11) wire ties
• three feet of ½" split loom
Installation Instructions
1. The sockets are installed into the back of both taillight as-
semblies. Gaining access to the taillights varies from vehicle
to vehicle, but for many vehicles you can accomplish this by
removing an interior trim panel; for many pickup trucks and
SUVs you must unbolt the taillight from the outside.
2. Look for a location to mount the sockets inside the tail-
light housings. The mounting point should be as flat as pos-
sible and must meet the following conditions: 1) the sockets
must be installed underneath red lenses; and 2) there must
be at least ¼" clearance between the bulbs and the lenses.
Install the bulb sockets underneath red lenses. If
the sockets are installed under amber or clear lenses,
IMPORTANT NOTICE!
Safety Definitions
These instructions contain information that is very important to know and understand. This information is provided for
safety and to prevent equipment problems. To help recognize this information, observe the following symbols:
WARNING indicates a potentially hazardous situ-
ation which, if not avoided, could result in property
damage, serious personal injury or even death.
CAUTION indicates a potentially hazardous situa-
tion which, if not avoided, may result in property dam-
age, or minor or moderate personal injury.
CAUTION
CAUTION used without the safety alert symbol in-
dicates a potentially hazardous situation which, if not
avoided, may result in property damage.
NOTE
Refers to important information and is placed in italic
type. It is recommended that you take special notice of
these items.
Bulb and socket kit
with 6- to 7-wire power cord
part number 1551676-7
Installation Instructions
ROADMASTER, Inc. • 6110 N.E. 127th Ave. • Vancouver, WA 98682 • 800-669-9690 • Fax 360-735-9300 • roadmasterinc.com
All specifications are subject to change without notice.
Time Tested • Time Proven
855851-00 01.18
continued from preceding page
ground the towed vehicle, as shown in Figure 1.
To avoid grounding problems, attach the wire to any
good chassis ground, preferably directly to the frame.
CAUTION
Failure to establish a good ground between the
towed vehicle and motorhome could cause aftermarket
accessories to malfunction, damage to both vehicle's
electrical systems, and other consequential damage.
7. Route the other end of the wiring harness to the front of
the vehicle. Use a route that avoids the possibility of fraying
or melting the wiring against moving parts, sharp edges, the
fuel lines or hot components. (If the OEM wiring harness is
accessible, consider routing the harness alongside it.)
Where sharp edges cannot be avoided, use a section
of the included wire loom to protect the wiring; use one or
more wire ties to secure the wiring in place.
Route the wiring to avoid moving parts, sharp edges,
the fuel lines or hot components such as the engine or
exhaust system.
Wiring exposed by moving parts, sharp edges or hot
components may cause a short circuit, which can result
in damage to the vehicle’s electrical system as well as
other, consequential damage.
Wiring which is attached in close proximity to the fuel
lines may ignite the fuel.
8. If it was necessary to drill a hole, seal it with silicone
sealant after you have routed the harness through.
9. After you route the wiring harness to the front of the
vehicle, you will connect the 4-wire harness to the power
cord's electrical socket. First, you must choose a mounting
point for the included socket —
If the towed vehicle has a Roadmaster Series 4 or 5 EZ
Twistlock
™
baseplate, you will attach the socket to the built-in
mounting posts on the main cross brace.
Otherwise, choose a suitable point to attach the socket
bracket (mounting hardware not included) at the front of the
vehicle, near the center, on the driver's side.
Attach the socket mounting bracket.
10. Remove the rubber boot at the back of the 6-wire socket
and route the wire harness through the socket bracket and
boot.
Attach the wiring to the back of the 6-way socket, ac-
cording to the 6-wire diagram.
Note: leave a 12-inch service loop at the socket for future
modifications. Secure the service loop with one of the wire
ties.
Apply a clear silicone sealant around each wire entry
and set screw indentation to help weatherproof the socket
and secure the set screws.
Reattach the boot.
11. Use the included ½" machine screws and Nylock nuts
to attach the socket to the socket bracket.
12. If the tow bar has channel guides, route the 6- to 7-wire
power cord through the driver's side channel guide. Using
Figure 1
the wiring diagram as a reference, attach the 6-wire plug to
the power cord.
As with the socket, apply a clear silicone sealant around
each wire entry and set screw indentation.
13. Plug the power cord into the motorhome and towed
vehicle; test for proper lighting function.
Socket Pin
Number Circuit
1 ............... Ground
2 ............... Brake light (for separate-to-separate
systems only)
3 ............... Taillight
4 ............... Charge line (not used)
5 ............... Left turn
6 ............... Right turn
7 ............... Auxiliary (not used
front of 7-wire socket
front of 6-wire socket
Socket Pin
Number Circuit
1 ............... Brake light (not used)
2 ............... Auxiliary (not used)
3 ............... Right turn
4 ............... Taillight
5 ............... Ground
6 ............... Left turn
front of 6-wire plug
Socket Pin
Number Circuit
1 ............... Brake light (not used)
2 ............... Auxiliary (not used)
3 ............... Right turn
4 ............... Taillight
5 ............... Ground
6 ............... Left turn
Wiring diagrams
Both of the plugs on the power cord have been wired to
standard electrical codes. To ensure that their wiring matches
the sockets…
• …use the 6-wire diagrams to wire the towed vehicle's
socket and plug; and
• …before towing, use a circuit tester to confirm that the
wiring on the motorhome's 7-way socket matches the dia-
gram of the 7-way socket below.
/
